College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China.
Yunnan Animal Health Supervision Institute, Kunming 650201, China.
Genes (Basel). 2024 Jul 27;15(8):991. doi: 10.3390/genes15080991.
Atypical porcine pestivirus (APPV) can cause congenital tremor type A-II in neonatal piglets, posing a significant threat to swine herd health globally. Our previous study demonstrated that the Mut domains, comprising 112 amino acids at the N-terminus, are the primary functional regions of the E2 protein of APPV. This study identified 14 host cellular proteins that exhibit potential interactions with the Mut domains of the E2 protein using yeast two-hybrid screening. Using bioinformatics analysis, we discovered that the Mut domains of the E2 protein might exert regulatory effects on apoptosis by modulating energy metabolism within the mitochondria. We also conducted co-immunoprecipitation, glutathione S-transferase pull-down, and immunofluorescence assays to confirm the interaction between the Mut domains of the E2 protein and cathepsin H and signal sequence receptor subunit 4 (SSR4). Ultimately, SSR4 enhanced APPV replication in vitro. In summary, our study successfully elucidated the interactions between the Mut domains of the E2 protein and host cell protein, predicted the potential pathways implicated in these interactions, and demonstrated SSR4 involvement in APPV infection. These significant findings contribute valuable knowledge toward a deeper understanding of APPV pathogenesis and the role of the Mut domains of the E2 protein in this intricate process.
非典型猪瘟病毒（APPV）可引起新生仔猪先天性震颤 A-II 型，对全球猪群健康构成重大威胁。我们之前的研究表明，E2 蛋白的 Mut 结构域（位于 N 端的 112 个氨基酸）是 APPV 的主要功能区。本研究通过酵母双杂交筛选，鉴定出 14 种宿主细胞蛋白与 APPV E2 蛋白的 Mut 结构域可能存在相互作用。通过生物信息学分析，我们发现 E2 蛋白的 Mut 结构域可能通过调节线粒体能量代谢对细胞凋亡发挥调控作用。我们还进行了共免疫沉淀、谷胱甘肽 S-转移酶下拉和免疫荧光实验，以验证 E2 蛋白的 Mut 结构域与组织蛋白酶 H 和信号序列受体亚基 4（SSR4）之间的相互作用。最终，SSR4 增强了 APPV 在体外的复制。总之，我们的研究成功阐明了 E2 蛋白的 Mut 结构域与宿主细胞蛋白之间的相互作用，预测了这些相互作用涉及的潜在途径，并证明了 SSR4 参与了 APPV 感染。这些重要发现为深入了解 APPV 发病机制以及 E2 蛋白的 Mut 结构域在这一复杂过程中的作用提供了有价值的知识。
